a medical librarian's adventures in evidence-based living

HOW TO FIND A POST

HOW TO FIND A POST

If you came to this page from a Google search, click on Edit in the search bar on top of your screen. Then click on Find & type in the KEYWORD you are looking for, like CERTO. You'll get to the exact spot you are searching for.

July 04, 2008

Is Olive Oil the healthiest fat? In a word, no! It's a better fat, but not the best one.

-Dr. Dean Ornish-

Contrary to our hypothesis, our study found that omega-9 (oleic acid)--rich Olive Oil, impairs endothelial function after eating. If you've been using olive oil because you think it's healthy, it's time to think again.

-Dr. Robert Vogel-

This is so disappointing. I've been dipping my whole grain bread in extra virgin olive oil & balsamic vinegar and feeling "oh so virtuous"--as I soaked up every last drop of oil on my plate. Olive oil is essentially the only fat I eat & cook with. I love the stuff!

Finding out that olive oil is bad makes me feels the same as when I found out that the tooth fairy & Santa Claus were made up stories.

Truth be told--this isn't the first time I've heard this. It's just that now it's finally soaking in--just like olive oil on bread. About 4 or 5 years ago at a Grand Rounds on the benefits of a plant-based diet held at my medical center, I asked one of Dr. Esselstyn's proteges if olive oil is finally on the OK list--now that we know how healthy the Mediterranean Diet is for us.

"Absolutely not!", he said. "Olive oil, like any fat causes inflammation and harms blood vessels. The research is out there. No one is listening. No oil--no olive oil!" Needless to say, I ignored what he had to say.

"Olive oil has been shown to injure the blood vessel's endothelium (lining). Walnuts are OK-but not if you already have heart disease. You know, here's what I've discovered. If you tell someone with heart disease that walnuts are OK, before you know it they have a bowl of nuts on their coffee table, a bag of nuts in their car and on and on. Nuts are full of calories--which is the last thing you need to eat when you're trying to lose weight. I advise my patients against eating nuts for this very reason.", Dr. Esselstyn said.

Here's Why You May Want to Think Twice About Olive Oil

From Dr. Dean Ornish: It's 100% fat and 14% of it is saturated. At 120 calories a tablespoon it's very easy to eat too much of "a bad thing". It won't raise your LDL as much as butter or other saturated fats will, so it might look like it's reducing your cholesterol, but it's still raising it. It's just not raising it as much other fats would! It's the omega-3's that reduce inflammation and are "heart healthy", and olive oil has very little omega-3, maybe 1%. It's mostly omega-9, which has been shown to impair blood vessel function. Canola and flax seed oil are much higher in omega-3's--and are much healthier oils to use. Just go easy on them!.

From Dr. Robert Vogel of the University of Maryland: This is the study that convinced me! Back in 2000 Vogel based his study on the Lyon Heart Study, which is the big-time study that got us all to eat the Mediterranean Diet. He wanted to see how olive oil, salmon (fish oil) and canola oil actually affect the blood vessels. Using the brachial artery tourniquet test he had 10 healthy volunteers with normal cholesterol ingest 50 grams of fat, in the form of olive oil & bread, canola oil & bread, and salmon. Measuring their arterial blood flow before & after each meal Vogel could tell whether or not a meal was causing damage to the endothelial lining of the brachial artery, based on how the blood was flowing through the artery after the meal was eaten. The results really surprised him. The olive oil constricted blood flow by a whopping 31% after the meal; the canola oil constricted it by 10%; and the salmon reduced it by only 2%. Why should we care? Because when the arteries constrict, the endothelium (the vessel's lining) is injured, triggering plaque build-up, or atherosclerosis. Vogel RA. Corretti MC. Plotnick GD. The postprandial effect of components of the Mediterranean diet on endothelial function. Journal of the American College of Cardiology. 36(5):1455-60, 2000 Nov 1. Similar results have been found it later studies. This isn't just a one-hit wonder. Interestingly, walnuts, which have Omega-3's have also been shown to improve blood flow by 24% using the brachial artery tourniquet test. Go omega 3's!

How does olive oil constrict blood vessels?: Dr. Vogel discovered back in 1999 that a high fat meal blocks the endothelium's ability to produce that all important NITRIC OXIDE, which is a vasodilator and critical to preserving the tone & health of our blood vessels. When olive oil constricts the blood vessels it's because it's blocking the production of nitric oxide. Not a good thing!

From Dr. Lawrence Rudel of Wake Forest University Baptist Medical Center: Rudel ran a five year study feeding monounsaturated fat (similar to olive oil) and saturated fat to African Green monkeys. The monkeys metabolize fat in the same way as humans, so they're good stand-ins.. At the end of five years, their autopsies showed that the monkeys who were fed the high-oleic monounsaturated olive oil surrogate had higher HDLs (the good cholesterol) and lower LDLs (the bad cholesterol) than the ones fed the saturated fat diet. The big surprise here: Both groups had exactly the same amount of coronary artery disease. The higher HDLs & lower LDLs of the high-oleic monounsaturated oil (similar properties to olive oil) group were meaningless. Rudel later repeated the study on rodents, and got the same results.

From Dr. Caldwell Esseltsyn: Dr. E tells a story in his book about Rev. William Valentine of North Carolina who had a quintuple bypass in 1990. Since his surgery he followed a strict plant-based diet, dropping from 210 pounds to 156 pounds. For 14 years he maintained his weight & his diet. But by 2004 he started to experience a recurrence of angina, especially when he exercised. He promptly contacted Dr. Esselstyn after reading about his success in reversing heart disease in a health newsletter. Valentine wanted no part of a repeat bypass or other intervention. He assured Dr. E that he only ate whole grains, legumes, vegetable & fruit. A baffled Dr. E prompted him to repeat once again everything he was eating, leaving nothing out.

"He had forgotten to mention that he was consuming "heart healthy" olive oil at every lunch and dinner and in salads. It was what they call a Eureka moment. Immediately, I advised him to give up the olive oil. He did--and within seven weeks, his angina had completely disappeared." Dr. Esselstyn

Little known fact: Olive oil, which got its big "heart healthy" start with the Lyon Study, wasn't even used in the study. The study volunteers didn't like the taste of it, so canola oil was substituted for olive oil. All the benefit that we attributed to olive oil, was actually from Omega-3 enriched canola oil.

What does Dr. Dean Ornish advise?: The best oils are canola, fish oil (omega-3s), flaxseed oil & nonstick cooking sprays. Always in small amounts. Second best, and in very small amounts, is olive oil.

What does Dr. Caldwell Esselstyn advise?: When it comes to olive oil, canola or any oil--FORGET ABOUT IT. He does advise taking a tablespoon of flaxseed every day for omega 3's.What Am I Going to Do? Olive oil--forget about it, except in tiny amounts. (at least I say that right now) I admit it, I was using way too much of the stuff, and consuming far too many unhealthy calories than I needed. I thought that because my HDLs were so high I was in good shape. Just like the African Green monkeys, the olive oil could have been raising my HDLs, while all the while plaque was forming in my arteries. Still mulling over a bigger move in the direction of a vegan goody-goody. Except, of course, when I'm invited out!

Comments

Bless you or curse you, my dilemma at the moment, Deb! Thank you I will, however, for pulling all this great information together in an easy to digest format. I, too, will miss all that great olive oil. And now, I will have more reason to actually consume that flaxseed oil in the fridge, in small amounts, of course. Have a great week!

In a world of information overload, SUCCINCT SUMMARIES of this quality are in short supply. VERY NICELY DONE. I met with Dr. Esselstyn last spring and have several copies of his book. Other books cited on Happy Healthy Long Live web site are also on my short list.

As you said, everything in moderation so I'll keep enjoying extra virgin olive oil, thank you very much. If I slavishly followed every little prevention nugget floated out there I'd eventually starve to death albeit in a very healthful state I'm sure.

Hi Juanita,
Well it's been over 5 months since I wrote this--& I do still have olive oil on my counter--I just use it in much smaller amounts--and on occasion. I only rarely do the "bread dipped in olive oil thing" & I use it sparingly (I measure) when I cook with it.

I don't think anything is absolutely awful for you "once in a while" if you're eating mostly whole foods like greens, multi-colored veggies, fruits, beans, nuts, seeds & whole grains. Face it--olive oil is all fat, but a little does makes food taste good & keeps me satisfied. But it's not the miracle food that some people think it is.

When I read these findings (very well summed up in this blog post!) I see a wonderful reminder about living with moderation. It's incredibly easy to get tricked into thinking that one thing is the perfect food through marketing when, in reality, nothing is healthy in excess. In my opinion, this includes completely forgoing olive oil.

Glad to read these reports about Olive Oil. I am going to use less...too bad. I do have a couple of questions about both Canola Oil, and also Flax seed oil. I have heard that Canola oil was a 'gear' oil, and has to be detoxified for consumption, and that it is now safe to use because there is only a tiny bit of the toxin left, but I haver also heard that even that little bit of toxin, is accumulative in the body. Also I understand that Flax seed is great for us, but oxidizes within a very short time when broken out of its shells, - I heard within 15 minutes. To keep it from being oxidized, the manufacturers put the oil in dark bottles, but it seems to me this will not really work very well, and we will be consuming rancid oil, if we do not grind it out ourselves, and eat a few short minutes afterwards.

It's soy, not olive oil, but I think we might find similar things with soy. I've decided to stop drinking soy milk, or using it in my smoothies. I've found oat "milk" to be lovely tasting. (I didn't like Hemp, and rice milk doesn't feel as nutritious.)

I think only half my comment appeared in the "preview box"... The version I saw (and now I can't see it) was missing how sad I was and how I too felt like there was no Santa Claus. Olive oil is in my DNA and I don't know how I'll make my spaghetti sauce!

If you apply the logic that flax is good & its oil is good, you would think that since walnuts are good for us (in moderation) then walnut oil would be good.

I am definitely not an expert by any means, but I do know that too many omega-6s (linoleic acid) is not so good, and looking at Evelyn Tribole's (she's a registered dietitian & author & a healthy oil expert) Omega 6 tracker--walnut oil is very high in omega 6's--which are inflammatory. Maybe keep down to a little for taste--it's not supposed to be heated at high temps. Check out Evelyn's website/blog at: http://omega-6-omega-3-balance.omegaoptimize.com/ and see if she has an answer about walnut oil.

Doctors have recently been saying D3 was superior to D2 (the common form of D found in supplemented food), but recent research by Dr. Michael Holick has shown that both forms, D2 & D3, will raise vitamin D levels in the blood equivalently.

To read most latest post on Vitamin D, click here:

"Everything You Ever Wanted to Know About Vitamin D from the Expert, Dr. Michael Holick. How Much Do We Need? Why Is It So Hard to Get Enough? What About Breast-Fed Babies? Why Is It So Important for Good Health?"

Vegans usually obtain vitamin D from the action of sunlight on the skin or by taking fortified foods such as soya milk, margarine (all of which are fortified by law in the UK) and vitamin supplements which are made from yeast or other fungi. Fortified vegan products contain D2 (ergocalciferol). Foods with naturally occurring vitamin D are, however, usually animal derived containing the vitamin D3 (cholecalciferol).

The most significant supply of vitamin D (for omnivores as well as vegans) comes from the action of ultra-violet B light on sterols in the skin. Most people, including infants require little or no extra from food when regularly exposed to sunlight when the sun is high in the sky. Bright sunlight is not necessary; even the sky shine on a cloudy summer day will stimulate formation of some D in the skin, while a short summer holiday in the open air will increase blood levels of the vitamin by two or three times the amount.

I have been doing a lot of research over the past two weeks about the benefits of Olive Oil, Omega 3's, etc. I found information that states that oil is oil and Omega 3's raise your total cholesterol and LDLs. This can be because in the last couple of years huge amounts taken daily was recommended for lowering bad cholesterol. I found this info on different sites. Now as far as Extra Virgin Olive Oil is concerned, it is a part of the Mediterranean Diet which is touted as the most healthy way any one can eat. I decided to take less Omega 3s than I have been and use less Extra Virgin Olive Oil. I believe it is the excess that is harmful, but if these oils are used in moderation, I am sure they do more good than harm.

My wife pointed me to your site -- but it's already become overwhelming.
Too much information.

Can you come up with a sidebar or page that has just basic eating information for getting through the day, day after day?

I don't care about the sauces and seasonings, I'm old enough to have lost enough sense of smell I guess. Delicious is for youngsters, or else for people who have cooks or time to cook complicated stuff.

I'd eat broccoli and brussels sprouts and apples at every meal -- if I could get them. I will, as soon as I retire. It'll be a while yet. That's stuff a commuting officeworker can't find for lunch, or can't always have time to cook for breakfast and dinner

Meanwhile -- simplify, simplify. Please give some very basic "If you have to do the simplest food you can get, get this ...."

Can you please cite references for your statement that olive oil was not used in the Lyon diet study? The researchers (from France) said that both olive oil and canola oil were recommended to participants. Presumably, since the study authors are French, the participants would also be French. It makes no sense to say that olive oil was excluded because the participants didn't like the taste. It is well documented that the French use plenty of olive oil.

"In the Lyon Diet Heart Study, investigators tested a Mediterranean type of diet (total fat represented 30% of energy) focusing on the quality of the fat (olive and canola oils exclusively), an increased consumption of cereals, bread, vegetables, legumes, fruit and a moderately increased consumption of fish'61. The three trials had in common an increased intake of omega-3 fatty acids."

CONCLUSIONS: In terms of their postprandial effect on endothelial function, the beneficial components of the Mediterranean and Lyon Diet Heart Study diets appear to be antioxidant-rich foods, including vegetables, fruits, and their derivatives such as vinegar, and omega-3-rich fish and canola oils.

thank you so much for an extremely informative and comprehensive discussion on Olive Oil. Too often, people stream 140 characters of health advice and opinion. I really appreciate your clinical approach.

I was on a very low fat/oil diet for a few months trying to figure out a diet for MS and it was pretty bad - no, no energy at all and my skin got all flaky. It couldn't have done me any good. I was eating whatever fruit, veggie and grain I wanted and got a great variety. Avocado was limited to 1/8 per day, however. What does this couple say about a fat intake level necessary to synthesize fat soluble vitamins and keep an energy level up?

What about coconut oil? I've been reading a lot about it lately and have been substitutding coconut oil for olive or canola oil when cooking at high heat, espcially when baking as many vegan baking recipes call for oil.

I don't use flax seed oil--just ground flax seeds. Never ever heat flax oil!! Don't know much about the phytoestrogenic properties of flax--but perhaps you're referring to its high lignan content (highest of all plants) which is purported to be beneficial in preventing breast cancer--works as an "excess estrogen remover". Speaking off the top of my head here--haven't looked at that research in awhile.

After all of the hype that olive oil and Mediterranean diet was the best type of diet along with daily vitamins and now we are told that vitamins cut ones life short and olive oil is inflammatory and promotes cardiovascular disease! I'm exhausted trying to find answers to healthy living. Totally demoralized as I have taken vitamins for years as well as used olive oil while completely eliminating margarine/butter!

coconut oil seems to be different from all the others and is not processed in the same way. would you please go out and do the same level of research that you applied to above studies-i have researched it quite a bit and feel safe using it although i do have CAD and my doctor has put me on crestor-i relented and take a 5 mg. pill every other day. Nor am i sure that it is a good idea at all. i use coconut oil for my sauteing and in my baking-i warm it to melting point and substitute it for any other kind. even dr. mehmet oz has come out for it-i was surprised and grateful as he is a very good cardiologist, as has dr. stephen sinatra. will look for your response. thank you.

I have looked into coconut oil. The real research--in medical journals--is scanty. Just a few studies, & mostly animal studies. Honestly, in spite of what Dr. Oz says, I'd stay away. It's still a lot of calories--and highly saturated--even if it's a medium chain triglyceride. You don't need oil to saute and have delicious food. You don't need oil to bake--and bottom line: most baked goods are sugar, fat, & flour--not the top nutrient choices. Coconut oil might not be atherogenic--or inflammatory--I just don't know. But it's still highly caloric, and a fat that you can live without.

Thank you, Pat, for posting this. I emailed Margot personally with what I knew about coconut oil (just in case she didn't revisit this post for the answer)--and what I read in the research (there's very little)--but this is so much better. Jeff did a fantastic job--and now his link is up for anyone else to see who visits this post!

And now I have a handy response the next time this question comes up==which is will. People think (want to think) that coconut oil is a miracle food--maybe it is as a body lotion--but that's about it!